1Department of Diagnostic Radiology, Keimyung University Dongsan Medical Center, School of Medicine, Korea. sklee@dsmc.ac.kr 2Department of Pathology, Keimyung University Dongsan Medical Center, School of Medicine, Korea.
Published online: March 1, 2007.
ABSTRACT
PURPOSE: To examine the usefulness of the cystic change of the thyroid mass in the diagnostic differentiation of benign from malignant thyroid lesions. MATERIALS AND METHODS: We retrospectively analyzed the ultrasonographic (US) findings of 65 benign (30 follicular adenomas and 35 nodular hyperplasias) and 206 malignant (202 papillary carcinomas and 4 follicular carcinomas) lesions that had been confirmed by surgery. The cystic change was graded as 0 (mass without cystic change), 1, 2, 3 and 4 (cystic change less than 25%, 25-50%, 51-75%, and more than 75% of the volume of the mass, respectively). The incidence and grades of the cystic change of the benign thyroid lesions were compared with those of the malignant lesions. We also evaluated the US features of the cystic change to evaluate any differences between benign and malignant lesions. Statistical significance was assessed by Chi-square test. RESULTS: Cystic change was present in 47/65 (72.3%) of benign thyroid lesions (21/30 [70%] of follicular adenomas and 26/35 [74.3%] of nodular hyperplasias) and 16/206 (7.8%) of malignant lesions (14/202 [6.9%] of papillary carcinomas and 2/4 [50%] of follicular carcinomas). The grades of cystic change were grade 1 in 29/47 (61.7%), 2 in 2/47 (4.3%), 3 in 2/47 (4.3%), and 4 in 14/47 (29.8%) for benign thyroid lesions, and grade 1 in 14/16 (87.5%) and 3 in 2/16 (12.5%) for malignant lesions. In regard to the US features of cystic change, a large cyst with polypoid projection less than 1 cm in size and a large cyst with a peripheral rind of solid component were exclusively found in the benign thyroid lesions. In contrast, malignant lesions frequently presented as a mass with irregularly mixed, solid and cystic components, a solid mass with multiple cystic components, or a solid mass with one or two cystic components. CONCLUSION: Cystic change was more common (p < 0.0001) and more prominent in benign than in malignant lesions. A large cyst with polypoid projection less than 1 cm in size and a large cyst with a peripheral rind of solid component were exclusively found in the benign thyroid lesions. The cystic change was evaluated to be a useful sign in the diagnostic differentiation of benign from malignant thyroid lesions, although the size of the lesion must also be taken into account.
Print
facebook
twitter
Linkedin
google+
Download Citation
PDF Links
Full text via DOI 
